Floatless carburetor



Novo M 11950 A. c. RUSSELL 2,529,665

FLOATLESS CARBURETOR Filed May 12, 1947 INVENTOR.

Patented Nov. 14, 1950 UNITED STATES PATENT OFFICE FLOATLESS omnrms'ronAndrew Craig Russell, Shawnee, Okla. Application May 12, 1947, SerialNo. 741,409.

1 Claim. ((1261-60) This invention relates to devices in the nature of acarburetor for internal combustion, engines and has for its primary aimthe provision of a fuel mixing apparatus that is entirely automatic inits operation and devoid of the fuel chamber float present in commontypes of carburetors.

The most important object of this invention is to provide a carburetorsimilar in many respects to that disclosed in my previous issued U. S.Letters Patent No. 2,366,056, dated December 26, 1944, and to improveupon the carburetors shown in my co-pending applications Serial Numbers646,767, 691,944 and 710,519, dated February 11, 1946, August 21, 1946and November 18, 1946, respectively. This is a continuation in part ofsaid applications.

Another important object of this invention is the provision of acarburetor having a fuel bowl provided with an inlet connected with asource of fuel supply and an overflow pipe for carrying excess fuel backto the source of supply to the end that a continuous flow is presentwhen the carburetor is operating at less than full capacity.

A further object of this invention is to provide a carburetor having theaforesaid means for supplying fuel thereto and a valve assembly operableentirely by the extent of air flow through the carburetor.

A still further object of this invention is to provide a floatlesscarburetor for internal combustion engines having a tubular memberinterconnecting the carburetor housing and the fuel bowl and providedwith a plurality of passages for introducing air from the interior ofthe housing to the level of'fuel within the tubular member.

Another object of this invention is to provide a carburetor of theaforementioned type having a collar within the housing in circumscribingscrew-threaded engagement with the tubular member and .having a portionsurrounding and in spaced relation to the outlet ends of the aforesaidpassages, all to the end that air may enter the tubular member andmixing chamber therein at all times in an even, steady flow.

Many minor objects of this invention will be made clear or becomeapparent during the course of the following specification, referencebeing had to the accompanying drawing, wherein:

Fig. 1 is a vertical substantially central sectional view through afloatless carburetor made in accordance with my present invention; and

Fig. 2 is a cross sectional view taken on line 11-11 of Fig. 1, lookingin the direction of the arrows.

A hollow housing broadly designated by the numeral III is sectional andwhen assembled, presents an air intake I2, and an air outlet [4 which isin communication with a pipe not shown, leading to the intake manifoldof the internal combustion engine in the usual manner.

intake passage I2 is equipped with a butterfly valve It to control thecarburetor.

A fuel bowl l8 forms a part of the housing II and depends from thenormally lowermost wall 20 thereof. This fuel bowl l8 may be detachablysecured to the housing Ill in any suitable manner to present ahermetically sealed chamber for receiving the fluid from a source ofsupply.

The fuel bowl I! may be drained if desired, by removing a plug 22disposed in the normally lowermost wall of fuel bowl l8. An elongatedtubular member 24 disposed within the fuel bowl I! passes through anopening formed in the wall 20 of housing l0 and tinuous air passagethrough housing 10 which interconnects intake l2 and air outlet l4. Thistubular member 24 is provided with a pair of spaced apartsubstantially'parallel plates 26 and 23 for purposes hereinafter morefully described and the plate 26 underlies and is secured to the wall 20through the medium of screws or the like, not shown. The normallyuppermost end of this tubular member 24, or that portion thereof whichextends into the housing It), is externally threaded as at 30 to receivean internally threaded collar 32. The threads 34 of this collar 32 arein mesh with the threads 39 of member 24 to the end that rotation of thecollar 32 moves the lowermost end thereof toward and away from theinnermost face of the bottom wall 20 of housing III.

This collar 32 is provided with a plurality of longitudinal ribs 36 anda screw 38 is threaded into a threaded bore 40 formed in one wall 42 ofhousing l0. This screw 33 extends into the housing l0 and is incontacting relationship with the collar 32 when the screw 38 is in theoperative position. When the innermost end of screw 23 is in engagementwith collar 32, the ribs 26 prevent rotation of collar 32 with respectto the tubular member 24. When the collar 32 is set in the desiredposition, a lock nut 44 on the screw 33 amount of air entering theextends upwardly into the con- 7 asaaoes and disposed exterlorly ofhousing Ill, holds screw 22 in the operative position.

A pair of spaced apart substantially parallel posts 44 are slidablymounted within openings 44, II and 42 in wall 2|, plate 24 and plate 28respectively. A disc i4 disposed within the fuel bowl ll joins thelowermost ends of the posts 48 and the uppermost ends of these posts 40are joined by a closure 54 mounted within the passageway through housingl joining intake l2 and outlet l4. This closure member It rests upon thecollar 22 and cooperates therewith in substantially closing thepassageway through housing in when the assembly, including posts 46, isat the lowermost end of its path of travel as illustrated in Figs. 1 and2. A longitudinal bore 58 is formed within the member 24 and haspress-fitted or otherwise afilxed thereto a pipe 60 at its normallyuppermost end and this pipe 60 terminates within the housing III inspaced relation to the closure and the collar 32. The other end of thebore 58 has a tubular plug 62 threaded therein for slidably receiving atapered valve 64. This valve 64 substantially closes the opening throughthe plug 82 when the plate 54 is at the lowermost end of its path oftravel. The valve 64 rests upon the disc 54 joining the posts 46 and isactuated by the vertical reciprocating movement of posts 46, disc 54 andclosure member 56.

The longitudinal bore 58 formed in the member 24 is of reduced diameterintermediate the ends thereof to present a restricted passage 66. Aplurality of passages 68 extend downwardly and inwardly from housing illto interconnect the latter with the terminate at their inner ends above,and in spaced relation to the passage 88, and above the level of fuelwithin the bowl l8 and within the bore 42. The passage 66 serves tomaintain said level of fuel within bore 58 below the inner end ofpassages N.

The normally lowermost end of the collar 32 is providedwith a cavity illof greater diameter than the threaded bore 34 thereof and this cavityIII is in clrcumscribing spaced reationship to the normally uppermostand outermost ends of the passages 68, as clearly illustrated in Fig, 1of the drawing.

The operation of the valve 64 is similar to that disclosed in myaforesaid U. S. Letters Patent. This constitutes essentially an openingand closing of the valve 64 by longitudinal reciprocation thereof withinthe bore 58 through actuation of the disc 54. As a greater or lesseramount of fuel mixture is allowed to pass into the internal combustionengine through the operation of the butterfly valve between the car-'buretor and the manifold as above described, air passing through thehousing lo from inlet l2 into the air outlet l4, will raise and lowerthe member 58 from the collar 32, permitting such air to pass upwardlyaround collar 32 to mix with the mixture emanating from the uppermostend of the pipe 60. During operation of the internal combustion engine,air is free to flow into the bore ss through the passages 68 exceptduring choking when the butterfly valve I6 is moved to a position topresent a richer mixture.

As set forth in my U. S. Letters Patent No. 2,366,056, there is a levelof fuel within the bore 5' below the innermost ends of the passages 68,and as air enters bore 58 it strikes the shoulder therein, produced bythe reduced passage 66 thereof and creates a turbulence. This turbulentair acts upon the level of fuel in bore 58, and the interior of bore 58.These passages 68 mixture is moved toward the outlet end of pipe 44 bysuction in the mine.

Collar 22 prevents a direct flow of air from the housing is into thebore 40, the passage being somewhat circuitous and, therefore, equalizedpressure is attained before entrance of the air into bore 52;

It is through use of the assembly just described that it is possible toeliminate the usual type of float within the fuel bowl ll. In lieuthereof, this carburetor is provided with an inlet opening 12 forreceiving a conduit 14 having connection with the usual type of fuelpump not shown, which receives fuel from a source of suply in the usualmanner. A fitting It communicating with the fuel bowl is below theintake opening 12 has connection with an overflow pipe 18. This overflowpipe has the opposite end thereof connected to the conduit which joinsthe fuel pump of the internal combustion engine with the fuel tank. whenthe engine is idling and the fuel pump is operating, a continuous flowof fuel passes from the fuel pump through the conduit I4 into theopening 12 and finally into the fuel bowl is. The carburetor, duringsuch idling operation of the engine, uses only a small amount of thefull capacity of the fuel pump and the conduit 14 and such excessoverflows into the pipe 18 and empties back into the pipeinterconnecting the fuel pump and the fuel tank. As the amount of fuelbeing used by the internal combustion engine is increased through theoperation of the carburetor just above described. the extent of overflowof fuel into the pipe 18 progressively decreases. Obviously, the totalcapacity of the conduit 14 is greater than the total capacity of theoverflow pipe 18 and by the same token, when the carburetor is operatingat full capacity, the capacity of the conduit 14 is such as to maintaina level of fuel in bowl is substantially as shown in Figs. 1 and 2. Inother words, as the greatest amount of fuel which may pass through thebore 58 of member 24 is reached, the extent of overflow of fuel from thepipe 18, decreases. It is seen, therefore, that during operation of thecarburetor, the fuel bowl I! always contains enough fuel to supply bore58, 68 and as the valve 64 is moved toward the closed position, anincreasing amount of fuel will overflow into the pipe 18. Thus the levelof fuel in bowl [8 will vary slightly during operation, particularlyduring rapid acceleration changes, but will never raise or drop to agreat extent with respect to overflow pipe 1!.

Formation of the carburetor as just described, eliminates manyunnecessary parts which decreases the cost of production substantiallyand provides for a more efficient operating carburetor generally.

The elimination of means for actuating the collar 22 as provided in myaforesaid U. S. Letters Patent, as *well as omission of the float withinthe fuel bowl l8, obviates the need of a multitude of parts that wouldotherwise tend to cause trouble because of maladjustment and otheroperating defects. Furthermore, it has been found that the carburetor asherein disclosed, operates as efficiently with these parts eliminatedand has the same advantages with respect to economy and excellence ofperformance as the carburetor forming the subject matter of my aforesaidpatent. In addition, the improvements herein set forth increases economyof operation, decreases initial cost of production of the carburetor andenhancessmooth operation.

I the fuel bowl and extending into the housing through said one wallthereof, said tubular member having a mixing chamber formed therein anda plurality of passages disposed to direct air from the housing intosaid mixing chamber and thence downwardly against the surface of fueltherein, the improvement of which includes a collar having an outturnedflange at the upper end thereof and a plurality of grooves formed on theperiphery of the collar below said fiange,said

grooves being parallel to the axis of rotation of the collar, a portionof the collar being in circumscribing relationship with the tubularmember adjacent the outermost ends of said passages and spacedtherefrom; a movable annular valve in the passage and resting on saidflange when at one end of its path of travel; a second valve operablyjoined to the first valve for controlling the flow of fuel from the bowlto the mixing chamber, said collar being threadably mounted on thetubular member for adjusting the position of the valves at said one endof the path of travel; and a set screw threadably mounted in the housingfor engagement with said grooves whereby said collar is releasably heldfrom movement out of adjustment.

ANDREW CRAIG RUSSELL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,333,982 Jensen Mar. 16, 19201,783,273 Beach Dec. 2, 1930 2,271,113 Bracke Jan. 27, 1942 2,366,056Russell Dec. 26, 1944

